Optical fiber transmission systems, in many instances, involve one or more panel mountings wherein a plurality of optical fiber connectors on one side of the panel are connected to a plurality of connectors on the other side of the panel through modular members such as adapters or buildouts or similar pass through devices. Desirably, such devices for holding connectors are mounted in the panel, but the connectors themselves are not connected to incoming or outgoing fiber paths until needed to provide service. The devices which are used to accommodate interconnections are referred to as couplings which, as pointed out, may take the form of adapters or a buildout system, which is a form of adapter and most often comprises a buildout block and a buildout member which, together form a buildout system.
There are, in the prior art, a number of different types of ferrule connectors, there being no universally accepted standard ferrule connector. Among these are the ST connector, shown in U.S. Pat. No. 4,934,785 of Mathis et al, the SC connector, shown in U.S. Pat. No. 5,212,752 of Stephenson et al., and other connectors such as the FC or LC connectors. Desirably, an interconnection arrangement, such as the buildout system, should be capable of accommodating each type of connector in any combination. A buildout system which is capable of accommodating ST as well as FC connectors is shown in U.S. Pat. No. 5,067,783 of Lampert. Each buildout block includes a tubular portion and provisions for receiving a buildout which is adapted to receive an ST connector or an FC connector. Thus, the connection may be between like connectors or between different connectors.
In U.S. Pat. No. 5,274,729 of King et al. there is disclosed a universal optical fiber buildout system which can be tailored for connection between any desired pair of connectors, whether of the same type or different types, in any desired combination. The buildout system of that patent includes a buildout block for insertion in an aperture in a panel and having a portion extending from one side of the panel for receiving an optical fiber connector. Any one of three buildout blocks may be used in order to receive an ST, SC, or FC connector. Secured to the buildout block by means of a latching arrangement is a buildout which extends from the front side of the panel and is configured to receive any one of the three types of connectors. The latching arrangement between the buildout block and the buildout is the same for any combination thereof. All of the combinations shown are for individual coupling, with each buildout block having an assigned aperture in the panel. Thus, while accomplishing the desired end of versatility or accommodation of different types of connectors used on either side of the panel, the individual arrangement make the assembly of a high density connection arrangement tedious.
In U.S. Pat. No. 5,123,071 of Mulholland et al., there is shown a buildout system for duplex connector arrangements in which an adapter comprises first and second substantially identical buildout blocks connected back to back for receiving duplex push-pull type connectors, which arrangement apparently lacks the universality of the King et al. arrangement, as well as apparently not being adaptable to high density applications. In U.S. Pat. No. 5,418,875 of Nakano et al. there is shown an adapter comprising first and second members connected together for receiving optical connectors. The arrangement is shown as being adaptable for high density applications, but no details of such an application are set forth.
In U.S. patent application Ser. No. 08/857,402 of Stephenson, filed May 16, 1997, and assigned to the present assignee, there is disclosed a buildout system which allows for the buildouts and the connectors to be assembled without the necessity of rotational movement, requiring only straight line push and pull for making or breaking connections. As a consequence, the connectors can be readily used in high connector to density applications using ganged fiber coupling buildouts. In a ganged configuration, the buildout latches to the buildout block and the buildout block latches to the panel, thus there are numerous latching members in the assembly. The Stephenson arrangement represents a large step forward in the gang mounting of connectors in high density applications. However, under certain circumstances it would not appear to be necessary to use a high density coupling arrangement of the complexity of the Stephenson arrangement where economy of the connecting structure is a consideration, and where simplicity is much to be desired.